This invention relates to a folding or collapsible keyboard which comprises foldable divided keyboard parts with a cover plate covering the severed or parted surfaces of the keyboard which are exposed when folded.
Folding keyboards have been proposed which comprises keyboard parts divided along a boundary line between the adjacent keytops located generally in the center of the keyboard so as to be foldable into a compact size when carried. The Japanese Patent Kokai Publication No. 2000-56904 discloses an example of the folding keyboard of such type in which the severed surfaces of the keyboard exposed when folded are adapted to be covered by a cover plate.
The folding keyboard as disclosed in this Patent Publication will now be briefly described with reference to FIGS. 1-3. FIG. 1(a) illustrates the keyboard 1 comprising divided keyboard parts 2 and 3 separated along a longitudinal central line thereof and the divided keyboard parts 2 and 3 as being folded with the keytop sides facing inwardly toward each other. The divided keyboard parts 2 and 3 are connected together by a cover plate 71 and hinges 72, 73 and is adapted to be brought into the usable state by opening them on the opposite side from the cover plate 71 from the folded position shown in FIG. 1(a), as sequentially shown in FIGS. 1(b), (c) and (d).
Specifically, in this prior art folding keyboard it is to be noted as shown in FIG. 2 that one 3 of the divided keyboard parts 2 and 3 divided along a boundary line between the adjacent keytops located generally in the center of the keyboard 1 is pivotally connected at its cut edge to one of the opposite side edges of the cover plate 71 by the hinges 73 while a rectangular support plate 81 for the keyboard part 3 is pivotally connected on its one side to the other side edge of the cover plate 71 by the hinges 72. The support plate 81 is formed along its opposite side edges with a pair of ribs 82 extending parallel to the length of the keyboard 1 while the other divided keyboard part 2 is provided with guide grooves 83 (see FIG. 3) in its bottom surface adjacent its front and rear side edges such that the guide grooves 83 are slidably loosely fitted over the outside edges of the support plate 81 and the ribs 82. With this construction, the keyboard part 2 is supported retractably for movement into abutment with the opposing keyboard part 3 at the parted position along the ribs 82 of the support plate 81 longitudinally of the keyboard 1.
Lock levers 86 are pivotally supported by pins 87 on the divided keyboard part 3 on its outer surfaces adjacent the mating face for abutment with the divided keyboard part 2 and are biased by springs 88 such that the forward ends 89 thereof toward the divided keyboard part 2 are inwardly urged. The forward ends 89 of the lock levers 86 are provided with inwardly angled pawls 89a. The divided keyboard part 3 is formed with guide ribs 85 which extend in opposition to and co-extensively with the respective guide ribs 82 in the open position of the divided keyboard parts 2 and 3 as shown in FIGS. 2 and 3 such that as the divided keyboard part 2 is moved toward the divided keyboard part 3 in the direction shown by the arrow, the divided keyboard part 2 is brought into abutment with the severed face of the divided keyboard part 3 while the guide grooves 83 are fitted over the guide ribs 85 and the pawls 89a at the forward ends 89 of the lock levers 86 come into engagement within the corresponding catch recesses 84 formed in the side surfaces of the divided keyboard part 2 whereby the divided keyboard parts 2 and 3 are integrated together.
From the folded state of the divided keyboard parts 2 and 3 as shown in FIG. 1(a), they are rotated into the horizontal position as shown in FIG. 1(c) via the position shown in FIG. 1(b) by opening their ends opposite from the coupled ends in the direction shown by the arrows. In that horizontal position, the divided keyboard parts 2 and 3 are moved toward each other in the direction shown by the arrows until the severed faces of the divided keyboard parts 2 and 3 come into abutment whereupon the divided keyboard parts 2 and 3 are secured together in the same plane by the latch mechanism 75 comprising the lock levers 86 and the catch recesses 84 to assume the usable position as shown in FIG. 1(d).
The prior art folding keyboard illustrated requires not only the hinges 72 for pivotally connecting the support plate 81 and the cover plate 71 but also the mechanism for allowing the divided keyboard part 2 to slide along the guide ribs 82 in order that the cover plate 71 for covering the severed surfaces of the divided keyboard parts 2 and 3 which are exposed in the folded position as shown in FIG. 1(a) may be flexible with respect to the divided keyboard parts 2 and 3. Consequently, the prior art folding keyboard was awkward in the opening and closing operations for changing the state between the folded position and the usable position which required two operations, the rotating operation and the sliding operation. In addition, the construction requiring such two operations has the drawback that it is mechanically susceptible to failure.
Accordingly, an object of this invention is to provide a folding keyboard which provides for effecting the opening and closing operation in one operation and hence which is mechanically sturdy.
According to this invention, the keyboard comprises two keyboard parts divided along a boundary line between the adjacent keytops located generally in the center of the keyboard, an elongated cover plate pivotally attached on one side edge thereof to the lower portion of the severed surface of one of the two divided keyboard parts, opposed brackets bent and extending in the same direction from the opposite end edges of the cover plate, opposed slide pins planted in the brackets toward the other side edge of the cover plate, and elongated grooves formed in the outside surfaces of the opposite side panels of the other divided keyboard part for slidably receiving the corresponding slide pins. The folding keyboard further includes moving links having elongated slots in which pins provided on the opposite side panels of each of the divided keyboard parts are slidably and loosely fitted.